Who do you call sir [or ma'am] when you are out of uniform?

Multiple choices, When I was on active duty you would salute and use the Sir or Ma'am address for any Officer whom you recognized as an Officer. Commissioned or Warrant. But also even today I use this form of address for anyone I initially meet or whom I have respect for. Unless of course they have a title that they have earned such as Congressman.....Or Mayor....Yet there were times when you could let your hair down so to speak and You could call you Officers by their Rank. Certain Company Commanders were Called Captain by their NCO's depending on the situation, and most of my Platoon leaders got L T behind closed doors.... We even had one Lt who got promoted to Cpt and stayed in the unit who was called X L T....

My mom taught me to be polite and civil to each and every person I met, regardless of station or rank because you are never wrong that way.

Everyone when I first meet them, then again if I can't remember their names.

Background, or the rest of the story as Paul Harvey used to say on the origins of Sir and Ma'am from the Oxford Dictionary.
The term Sir dates back to the 1300 or so to "honor of a knight or baronet (until 17th century was also a title of priests). Generalized as a respectful form of address by mid-14th century and used as a salutation at the beginning of letters from early 15th century.
The term Ma'am a contraction for Madame dates back to the mid 17th century.
http://community.oxforddictionaries.com/boards/topic/origin-of-the-word-sir/
COL Mikel J. Burroughs, TSgt Hunter Logan, SGT Forrest Stewart, SGT Randal Groover, SPC Margaret Higgins

Everyone should be addressed sir/ma'am when not in uniform. Common courtesy. When in uniform address the individual appropriately.

Everyone, even the sandwich artist at Subway gets respect from this guy. How I was raised and how I raise my children. My two cents.

I call everyone sir or ma'am. That was drilled into me growing up. If I knew them well enough it was Mr./Mrs./Miss whoever. The only time I ever had a problem was if I accidentally referred to someone by the wrong gender. The most embarrassing was about a week before basic training doing some volunteer work, everyone I was working with was a man except the director of the charity. So after a full day of yes sir, no sir when I was introduced I proudly said "Pleased to meet you sir." She wasn't amused, I apologized and a friend explained I was about to leave for the military and was going to be saying sir a lot in the near future, it seemed to calm her a little bit.

I address all those that I recognize are officers both in and out of uniform as well as NCOs senior to myself. And being kid raised in NC, I greet those older than myself as Sir or Ma' am.

LTC Stephen F. Virtually anyone I don't already know well, and many that I do.

Anyone I don't know socially.